Version details: 2.12.1

See the three screehshots:

When gnome-control-center starts up, it shows some icons and the text under
them is perfect (1st screenshot).

For some of these icons, when I move the mouse over this icon, the text below
gets corrupted, that is, parts of the text is moved 1 pixel to the right or to
the left (2nd screenshot).

The differences are marked on the 3rd screehsnot. After the letter "A" of
"Alapértelmezett", and in the middle of letter "M" of "Munkamenetek" an extra
pixel column is inserted and the rest of the text goes one pixel to the right.

In "Képernyő felbontása" "K" remains okay, for the following letters (except
the last 1.5 letters) the upper part of the text is shifted 1 pixel to the
right, while for the last one and a half letters (the right side of "s" plus
the whole "a") the upper part stays at its place and the lower part goes one
pixel to the left.

When I click on an icon (the text is printed with white on blue (Bluecurve)),
the text remains buggy, but then if I click on another icon, then the text
which is now repainted from white-on-blue to the standard black-on-white gets
repaired.

Similar bug occurs in most of the icon labels if another window is slowly moved
over the control-center window so that it receives partial expose events.

I have LANG=hu_HU.UTF-8 but the bug also occurs with en_US or C.

The last Gnome version I used was 2.8 prior to this 2.12 now, and I don't
remember seeing such a bug there.

I am not sure if the bug resides in control-center itself and not in a
library used by cc. However, I didn't see any font rendering problems in any
other applications, so I suspect that the bug is in cc, not in some low-level
libraries. Amongst others, nautilus itself (with the same "icon plus labels
(filenames) below the icons" view) works perfectly, I couldn't trigger this bug
in nautilus.